This thesis explores the integration of solid sorbent direct air capture (DAC) with two types of concentrated solar power, to create a renewable and scalable approach for carbon dioxide removal. Parabolic trough collector (PTC) and solar power tower (SPT) systems are modelled dyn
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This thesis explores the integration of solid sorbent direct air capture (DAC) with two types of concentrated solar power, to create a renewable and scalable approach for carbon dioxide removal. Parabolic trough collector (PTC) and solar power tower (SPT) systems are modelled dynamically on an hourly basis, combined with the energy requirement and performance of the DAC model. Because system output is highly sensitive to climatic conditions, two high-irradiance locations in Almeria, Spain and Alice Springs, Australia are evaluated using typical meteorological year data.
The results show that SPT outperforms PTC in achieving the lowest levelised cost of CO2 removal (LCOD), primarily due to its lower thermal energy storage costs. The configuration optimised for LCOD involves significant oversizing of the solar field and storage, far larger than the configuration optimized for cost of heat. This increases the capacity, and utilises the CAPEX-intensive DAC installation to a greater extent. These DAC costs are the main cost driver accounting for 68% of the cost for a conservative scenario. A sensitivity analysis reveals that lowering the DAC costs is found not to change the optimal configuration significantly, allowing the LCOD of a lower CAPEX scenario to be determined accurately from the results.
The weather conditions in Alice Springs result in a reduction of the LCOD by up to 27% compared to Almeria, due to higher and more constant solar availability combined with lower humidities. While PTC systems have higher LCOD, they require significantly less land. Overall, the combination of CSP and DAC is technically viable and it offers a scalable, land efficient alternative to nature based carbon dioxide removal methods.